as long as you're still on stock ROM and didn't add any mods like the webtop mirroring, etc you should be fine to flash without having to SBF back to stock. I just went straight from stock rom to ginger
you need to download the CWM package file first...then install it in your phone...
CWM gives you the recovery options
then to install gingerblur. you put the zip file in the SD card...boot into recovery and install from there